Patent GB-656281-A (GB)
Title: Improvements in or relating to telephone or like systems
IPC: H04Q3/00
Filed: 1948-09-09
Abstract: 656,281. Automatic exchange systems. AUTOMATIC TELEPHONE & ELECTRIC CO., Ltd., and RICE, T. G. Sept. 9, 1948, No. 23717. [Class 40 (iv)] In a register-translator the two code digits (B and C digits) are registered on a single bridge unit of a cross-bar switch and subsequent digits are each registered on a different bridge unit. One of the bridge units not used for registering digits is automatically operated to effect the retransmission in translated form of the code digits and the retransmission of the numerical digits. Cross-bar switch. The switch employed is of the 10 x 10 type having ten bar magnets IS, 2S ... 0S and ten bridge magnets 1B, 2B ... OB. The bar magnets are associated in successive pairs, each pair controlling an axially pivoted vertical bar which is turned slightly clockwise or anti-clockwise about a mean position according to the magnet energized. The bridge magnets are associated with individual horizontal bars which may be turned slightly when the relevant magnet is energized. Ten banks of contacts referred to as bridge units are provided and are designated 1BU to 0BU, only 1BU and 3BU being shown in their entirety. In the embodiment shown, each bridge unit comprises eight horizontal stationary common contact strips, referred to as commons, and ten columns of individual movable contact springs, each of which may be brought into engagement with the common immediately above it. More or less than eight commons and contacts may, however, be included as required. A column of contacts is actuated when a bar magnet and a bridge magnet are actuated in turn and may be considered as being in a co-ordinate position relative to the operated magnets, e.g. bar magnet 4S and bridge magnet 3B operate the fourth column of bridge unit 3BU and this will be referred to as column 4/3. In the usual register-translator systems the designation plates on the subscriber's telephone dial preclude the use of digit " 1 " as a code digit, so that the B and C digits may be registered on the appropriate one of bridge units 2BU to 0BU, but 1BU remains available for other purposes. Eight bridge units are available for storage of the numerical digits. Seizure of register-translator. This occurs over the A-digit selector level corresponding to the A-digit dialled and ground applied to the P lead brings up relay A, which holds to a full ground applied later to the PU lead and operates relay B. B-digit dialled. The impulses are received over the PU lead and relay A responds, C coming up for the duration of the train on the first release of A and being followed by CA. This first release of A also brings up bar magnet 1S which holds temporarily under control of A and in turn operates E which locks up and disconnects the operate circuit of 1S. The re-operation of A removes the short-circuit from the right-hand winding of D which pulls up in series with 1S. The second release of A holds D and brings up 2S which disconnects IS, and when A re-operates at the end of the second impulse D falls away. Thus as the B digit is dialled the bar magnets are operated singly and successively in the order 1S to 0S, D being released to extend the repeated earth pulse to the odd bar magnets, and operated to extend it to the even bar magnets. Eventually the bar magnet appropriate to the digit dialled is operated and if the digit is odd D remains up at the end of the train. The consequent relapse of C releases CA and brings up F which disconnects the impulsing paths to the bar magnets, releases D if it is up, and holds the operated bar magnet. C-digit dialled. Relay A responds as before, its first release bringing up 1B which releases E, and its re-operation at the end of the impulse allowing D to operate in series with 1B. The second release of A holds D and brings up 2B which releases 1B, and the second reoperation of A releases D. Here again D is down during each odd release of A and up during each even release so that the bridge magnets are operated sequentially. The bridge magnet corresponding to the C digit dialled is eventually operated and holds directly if the digit is even, or in series with D if it is odd. The appropriate column of bridge unit contacts is thus operated, e.g. if digits " 4 " and " 3 " have been received the column 4/3 is operated. At the end of the C digit train, C and CA again release and the consequent operation of relay SS releases F, the operated bar magnet, and relay D (if up), holds the operated bridge magnet and brings up SR. The operation of SR prepares a circuit for UD and DD which is completed if the operated bridge magnet is 3B, 5B, 7B or 9B, and operates the bar magnet immediately preceding that previously operated, e.g. in the case under consideration 2S. The operation of the bar magnet brings up 1B which locks up and releases SR. If the C digit is odd as in the present instance, UD and DD operate in series when SR comes up.and prepare the impulsing circuit to the bridge magnet which is to register the first numerical digit. If the C digit is even DD and UD remain down and the first numerical digit is registered on the odd bridge magnet immediately following that taken in use by the C digit unless the C digit is " 0 " when operation of 0B ensures that it will be registered on 2B. On the release of SR, UD and DD hold (if up) and the operated bar magnet (2S) is released, the associated column (2/1) remaining actuated under control of 1B. A marking earth is now extended over arc CN5 contact 1, lower common and contact in columns 2/1 and 4/3 to terminal TA in the translation field TRANS and the circuit is conditioned to commence translation. This feature will, however, be described later. Numerical digits dialled. Relay A responds to the impulses of the first numerical digit and repeats them to the bar magnet chain IS to 0S as was the case for the B digit, the operating circuit for D and the holding circuit for the odd bar magnets being modified slightly. When C relapses at the end of the train TP comes up during the release time of CA and at the same time ground is extended over CA front and C back contacts to operate 4B. The column of contacts in 4BU appropriate to the value of the first numerical digit is thus actuated and a particular contact in 4BU, one of the group of ten extending to terminals NC, is brought into contact with its associated common. This contact is thus extended to the corresponding one of terminals T1 to T0 in the translation field TRANS. The momentary operation of TP releases the operated bar magnet and if need be relay D as well. During the release time of CA relays UD and DD fall away, preparing the circuit for registering the next digit. The second numerical digit is received by the bar magnets in like manner and 5B is operated at the end of the train so that it is registered in 5BU (not shown). The release of C also brings up UD so that when CA relapses DD is re-operated to prepare a circuit to 6B for registering the next digit. The third and fourth numerical digits are repeated in turn to the bar magnet chain and stored by bridge magnets 6B and 7B respectively. Pulsing-out. The routing number may comprise up to six digits and is followed by the four numerical digits. Interrupters AIMP and BIMP which are continuously actuated, e.g. by motor-driven cams, each close 10 times per second for substantially complementary periods, AIMP providing 33 per cent make and BIMP 66 per cent make. As soon as the B and C digits are stored (relay SS and magnet 1B operated), ground is connected to contact CN2/1 and when BIMP next open the short circuit is removed from IG which operates and energizes uniselector magnet CNM. On the next closure of BIMP, magnet SSM is energized and is afterwards de-energized when BIMP re-open, whereupon the uniselector SS steps to position 2. This uniselector continues stepping at ten steps per second under control of BIMP in search of the first translated digit marking appearing in arc SS2 which is determined by the cross-connection from terminal TA. With SS in position 3 the original loop applied to the + and - pulsing-out conductors leading to the A digit selector ADS is replaced by one including interrupter AIMP and from then on looppulses at the rate of ten per second are sent out as SS continues stepping. When the marked contact of SS2 is reached, SZ pulls up, short-circuits AIMP, releases IG, de-energizes CNM to step CN to position 2, and disconnects relay CO. The release of IG completes a selfdrive circuit for SS to position 15 and later from position 19 to home. From positions 15 to 19 SS steps under control of BIMP to ensure an adequate inter-digital pause, IG re-operating on the first break of BIMP and preparing for operation of SSM on the next make. When SS reaches home the original loop condition is re-applied to the + and - conductors and SZ is released. Relay IG pulls up to ground over CN2/2 on the next break of BIMP, and ground is extended over CN5/2 to terminal TB and thence by the cross-connection to mark the second translated digit in arc SS2. The second and subsequent translated digits to a total of six are transmitted in a similar manner to the first. The control uniselector steps once after each digit is sent, thus reaching position 7 where a self-drive circuit is completed over arc CN3 and CN steps until a marking earth extending from the seventh common and associated contact in column 2/1 to arc contact CN1/9 brings up NSP which stops CN (in position 9 in this case) and grounds wiper CN4. Since the first numerical digit is stored in 4BU a particular column in that unit is actuated and the ground now connected over arc contact CN5/9 and common 7 of 4BU is extended to a particular terminal in group NC. This terminal is permanently connected to an equivalent terminal in the group T1 to T0 and a marking earth is applied to the SS2 arc contact appropriate to the first numerical digit. Since the code digits are still stored in 3BU ground